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Eutrophication is manifested by increased primary production leading to oxygen depletion in near‐bottom water and toxic cyanobacteria blooms. This is an important contemporary problem of the Baltic Sea and many other coastal waters. The present eutrophication is mainly ascribed to anthropogenic activity. To compare the present trophic state with that during past millennia, two sediment cores (50 cm long and ~400 cm long covering ca. 5,500 years) were taken from the Gulf of Gdańsk (southern Baltic Sea). The core subsamples were analyzed for phytoplankton pigments (chlorophylls and their derivatives, and carotenoids). In addition, carbon (Ctot, Corg, and δ13C), 14C dating, grain size, diatoms, and selected metals in the cores were analyzed to determine conditions in the depositional environment. The results indicated that there were high primary production periods in the past, during the Littorina Sea and the Roman Climatic Optimum, accompanied by oxygen deficiency in the near‐bottom water, most probably caused by climate warming. The ratio of 132,173‐cyclopheophorbide‐a enol, a labile degradation product of chlorophyll‐a, to the sum of other chloropigments‐a (CPPB‐aE/ΣChlns‐a) is proposed as a new paleoredox proxy. Heterocystous cyanobacteria blooms of an intensity similar to or even greater than at present also occurred in past millennia and were connected with climate warming. Hence, eutrophication must have occurred in the past, which means that natural factors have a substantial influence on it. Key Points: Eutrophication is not only a present‐day anthropogenic phenomenon in the southern Baltic; it also occurred in the past few millenniaHeterocystous cyanobacteria blooms in the past few millennia were connected with climate warmingThe ratio of 132,173‐cyclopheophorbide‐a enol to the sum of other chloropigments‐a in sediments is a good, new paleoredox proxy [ABSTRACT FROM AUTHOR]

The period around 50 000–35 000 years ago constitutes one of the most debated research issues in European archaeology of the Palaeolithic. In this time period, the transition from the Middle to the Upper Palaeolithic took place. Locally, in different areas of Europe, this shift is recorded in so‐called transitional assemblages. The eastern fringe of these transitional assemblages is represented by the Jerzmanowician, the unit described on the basis of a lithic assemblage from Nietoperzowa Cave (Poland). The unit is a part of a European transitional complex called the Lincombian–Ranisian–Jerzmanowician. Up to now, the radiocarbon dates presented in the literature have only allowed us to set the age of the Jerzmanowician at c.40 000–45 000 ka cal bp. In this study, we present 42 new radiocarbon dates. We attempt to set the archaeological record of the Jerzmanowician from Nietoperzowa Cave in an accurate chronological framework, based on Bayesian statistical processing of radiocarbon dates. We conclude that the lower boundary of layer 6 in Nietoperzowa Cave can be statistically located in the range 44 000–42 000 cal bp and the upper limit for the Jerzmanowician is estimated to c.31 000 cal bp. New data raises a question on the correlation with upper layer 4. In the light of the new chronology, the attribution of the archaeological inventory from layer 4 to the Jerzmanowician seems questionable. [ABSTRACT FROM AUTHOR]

ABSTRACT A new record from the heart of the Moroccan Middle Atlas cedar forests spans the last 18 000 years and provides valuable insight into our understanding of the natural vegetation and environmental changes. The approach is based on the study of pollen content, geochemical elements and grain size analysis. The pollen data indicate that the vegetation was dominated by herbaceous plants until 9000 BP. Such open landscape allowed greater soil erosion and an input of chemical elements from the watershed. After 9000 BP, tree cover, mainly oak, increased slightly and was accompanied by a higher taxonomic diversity. However, several steppe elements remain well represented in the area until 5000 BP, which suggests that the climate was rather dry during the first part of the Holocene. After 6000 BP, the climate became more favourable to expansion of the forest ecosystems, including Cedrus atlantica, thereby reducing erosion. A strong reduction of the tree pollen percentages is recorded after 2000 BP, which may be related to increasing human activities during the Roman period. These forest changes are concomitant with an increase of lead and copper concentrations in the record, probably related to Roman metalworking activities. [ABSTRACT FROM AUTHOR]

Ecosystems across the globe are threatened by climate change and human activities. New rapid survey approaches for monitoring biodiversity would greatly advance assessment and understanding of these threats. Taking advantage of next-generation DNA sequencing, we tested an approach we call metabarcoding: high-throughput and simultaneous taxa identification based on a very short (usually <100 base pairs) but informative DNA fragment. Short DNA fragments allow the use of degraded DNA from environmental samples. All analyses included amplification using plant-specific versatile primers, sequencing and estimation of taxonomic diversity. We tested in three steps whether degraded DNA from dead material in soil has the potential of efficiently assessing biodiversity in different biomes. First, soil DNA from eight boreal plant communities located in two different vegetation types (meadow and heath) was amplified. Plant diversity detected from boreal soil was highly consistent with plant taxonomic and growth form diversity estimated from conventional above-ground surveys. Second, we assessed DNA persistence using samples from formerly cultivated soils in temperate environments. We found that the number of crop DNA sequences retrieved strongly varied with years since last cultivation, and crop sequences were absent from nearby, uncultivated plots. Third, we assessed the universal applicability of DNA metabarcoding using soil samples from tropical environments: a large proportion of species and families from the study site were efficiently recovered. The results open unprecedented opportunities for large-scale DNA-based biodiversity studies across a range of taxonomic groups using standardized metabarcoding approaches. [ABSTRACT FROM AUTHOR]

There is an ongoing discussion whether n-alkane biomarkers -- and organic matter (OM) from loess in general -- reflect a syn-sedimentary paleoenvironmental and paleoclimate signal or whether they are significantly a post-sedimentary feature contaminated by root-derived OM. We present first radiocarbon data for the n-alkane fraction of lipid extracts and for the first time luminescence ages for the Middle to Late Weichselian loess-paleosol sequence of Gleina in Saxony, Germany. Comparison of these biomarker ages with sedimentation ages as assessed by optically stimulated luminescence (OSL) dating shows that one n-alkane sample features a syn-sedimentary age (14C: 29.2±1.4 kyrcalBP versus OSL: 27.3±3.0 kyr). By contrast, the 14C ages derived from the other n-alkane samples are clearly younger (20.3±0.7 kyrcalBP, 22.1±0.7 kyrcalBP and 29.8±1.4 kyrcalBP) than the corresponding OSL ages (26.6±3.1 kyr, 32.0±3.5 kyr and 45.6 ±5.3 kyr). This finding suggests that a post-sedimentary n-alkane contamination presumably by roots has occurred. In order to estimate the post-sedimentary n-alkane contamination more quantitatively, we applied a 14C mass balance calculation based on the measured pMC (percent modern carbon) values, the calculated syn-sedimentary pMC values and pMC values suspected to reflect likely time points of post-medimentary contamination (current, modern, 3 kyr, 6 kyr and 9 kyr). Accordingly, current and modern root-contamination would account for up to 7%, a 3 kyr old root-contamination for up to 10%, and an Early and Middle Holocene root-contamination for up to 20% of the total sedimentary n-alkane pool. We acknowledge and encourage that these first radiocarbon results need further confirmation both from other loess-paleosol sequences and for different biomarkers, e.g. carboxylic acids or alcohols as further lipid biomarkers. [ABSTRACT FROM AUTHOR]

New attempts are presented to determine the age of large Pleistocene mammals excavated at Starunia, ∼130 km southeast of Lviv, Ukraine. This remarkable discovery made at the beginning of the 20th century included a complete carcass of woolly rhinoceros (No. 2), fragments of 3 woolly rhinoceroses (Nos. 1, 3, and 4) and remnants of numerous specimens of other fossil fauna and flora. Although attempts to date paleontological findings from Starunia site go back to the early 1970s, the results obtained before 2006 are somewhat misleading, mostly due to unresolved contamination problems. Comprehensive cleaning of the samples adopted in the framework of this study was aimed at removal of 2 potential sources of contamination: (i) radiocarbon-free hydrocarbons abundant at the burial site; and (ii) allochthonous organic materials containing contemporary carbon that were used in the past during preservation of the dated specimens. Two types of samples have been analyzed for their 14C content in the framework of the present study: (i) fragments of bones and teeth collected from specimens stored or exposed in the Natural History museums in Lviv and Kraków; and (ii) samples of terrestrial macrofossils retrieved from sediment cores obtained during the 2007-2008 field campaigns in the Starunia area. 14C analyses of collagen were supplemented by measurements of its elemental C/N ratio and 13C/12C and 15N/14N isotope ratios. Three 14C dates obtained for rhinoceros No. 2 span the age range from 35.3 to 40.0 ka BP, in agreement with the minimum age estimated from macrofossils. The mean value of 37.7 ± 1.7 ka BP falls in the range of ages reported for big Pleistocene mammals from other locations in Europe. The bones of rhinoceros No. 3, which were found in close vicinity to those of rhinoceros No. 2, reveal a 14C age of 36.7 ±?0.6 ka BP. The δ15N and δ13C values obtained for collagen extracted from bones and teeth belonging to rhinoceroses Nos. 1, 2, and 3 are in a broad agreement with analogous literature data for large Pleistocene mammals found in other sites in Europe, North America, and Siberia. [ABSTRACT FROM AUTHOR]

In the Gliwice Radiocarbon Laboratory, a system for preparation of samples for AMS dating has been built. At first it was used to produce graphite targets from plant macrofossils and sediments. In this study we extended its capabilities with the preparation of bones. We dealt with 3 methods; the first was the classical Longin method of collagen extraction, the second one included additional treatment of powdered bone in alkali solution, while in the third one carboxyl carbon was separated from amino acids obtained after hydrolysis of protein. The suitability of the methods was tested on 2 bone samples. Most of our samples gave ages >40 kyr BP, suggesting good performance of the adapted methods, except for one sample prepared with simple Longin method. For routine preparation of bones we chose the Longin method with additional alkali treatment. [ABSTRACT FROM AUTHOR]

Background: Among patients with acute myocardial infarction, cardiogenic shock, and multivessel coronary artery disease, the risk of a composite of death from any cause or severe renal failure leading to renal-replacement therapy at 30 days was found to be lower with percutaneous coronary intervention (PCI) of the culprit lesion only than with immediate multivessel PCI. We evaluated clinical outcomes at 1 year.Methods: We randomly assigned 706 patients to either culprit-lesion-only PCI or immediate multivessel PCI. The results for the primary end point of death or renal-replacement therapy at 30 days have been reported previously. Prespecified secondary end points at 1 year included death from any cause, recurrent myocardial infarction, repeat revascularization, rehospitalization for congestive heart failure, the composite of death or recurrent infarction, and the composite of death, recurrent infarction, or rehospitalization for heart failure.Results: As reported previously, at 30 days, the primary end point had occurred in 45.9% of the patients in the culprit-lesion-only PCI group and in 55.4% in the multivessel PCI group (P=0.01). At 1 year, death had occurred in 172 of 344 patients (50.0%) in the culprit-lesion-only PCI group and in 194 of 341 patients (56.9%) in the multivessel PCI group (relative risk, 0.88; 95% confidence interval [CI], 0.76 to 1.01). The rate of recurrent infarction was 1.7% with culprit-lesion-only PCI and 2.1% with multivessel PCI (relative risk, 0.85; 95% CI, 0.29 to 2.50), and the rate of a composite of death or recurrent infarction was 50.9% and 58.4%, respectively (relative risk, 0.87; 95% CI, 0.76 to 1.00). Repeat revascularization occurred more frequently with culprit-lesion-only PCI than with multivessel PCI (in 32.3% of the patients vs. 9.4%; relative risk, 3.44; 95% CI, 2.39 to 4.95), as did rehospitalization for heart failure (5.2% vs. 1.2%; relative risk, 4.46; 95% CI, 1.53 to 13.04).Conclusions: Among patients with acute myocardial infarction and cardiogenic shock, the risk of death or renal-replacement therapy at 30 days was lower with culprit-lesion-only PCI than with immediate multivessel PCI, and mortality did not differ significantly between the two groups at 1 year of follow-up. (Funded by the European Union Seventh Framework Program and others; CULPRIT-SHOCK ClinicalTrials.gov number, NCT01927549 .). [ABSTRACT FROM AUTHOR]

Background: In patients who have acute myocardial infarction with cardiogenic shock, early revascularization of the culprit artery by means of percutaneous coronary intervention (PCI) improves outcomes. However, the majority of patients with cardiogenic shock have multivessel disease, and whether PCI should be performed immediately for stenoses in nonculprit arteries is controversial.Methods: In this multicenter trial, we randomly assigned 706 patients who had multivessel disease, acute myocardial infarction, and cardiogenic shock to one of two initial revascularization strategies: either PCI of the culprit lesion only, with the option of staged revascularization of nonculprit lesions, or immediate multivessel PCI. The primary end point was a composite of death or severe renal failure leading to renal-replacement therapy within 30 days after randomization. Safety end points included bleeding and stroke.Results: At 30 days, the composite primary end point of death or renal-replacement therapy had occurred in 158 of the 344 patients (45.9%) in the culprit-lesion-only PCI group and in 189 of the 341 patients (55.4%) in the multivessel PCI group (relative risk, 0.83; 95% confidence interval [CI], 0.71 to 0.96; P=0.01). The relative risk of death in the culprit-lesion-only PCI group as compared with the multivessel PCI group was 0.84 (95% CI, 0.72 to 0.98; P=0.03), and the relative risk of renal-replacement therapy was 0.71 (95% CI, 0.49 to 1.03; P=0.07). The time to hemodynamic stabilization, the risk of catecholamine therapy and the duration of such therapy, the levels of troponin T and creatine kinase, and the rates of bleeding and stroke did not differ significantly between the two groups.Conclusions: Among patients who had multivessel coronary artery disease and acute myocardial infarction with cardiogenic shock, the 30-day risk of a composite of death or severe renal failure leading to renal-replacement therapy was lower among those who initially underwent PCI of the culprit lesion only than among those who underwent immediate multivessel PCI. (Funded by the European Union 7th Framework Program and others; CULPRIT-SHOCK ClinicalTrials.gov number, NCT01927549 .). [ABSTRACT FROM AUTHOR]